What Happens If Acceptance Testing Fails?
The system does not comply until the problem is corrected and the test is repeated. An acceptance certificate records a functional result, so there is no version of it that documents a failure and still satisfies the requirement.
Why a failure cannot be documented around
The certificate exists to record that an installed system performed as required when tested. The authority having jurisdiction requires it to demonstrate compliance. So a failing test does not produce a certificate with a bad result on it — it produces no usable certificate until the deficiency is fixed and the test is run again.
What typically fails, and why
On lighting, zoning rather than hardware. A single occupancy sensor covering a large open office fails the requirement that control zones in offices over 250 square feet be 600 square feet or less, however well the sensor itself works. Daylighting credits fail when the feature claimed in the calculation was value-engineered out of the build.
On mechanical, sequences rather than equipment. Outdoor air controlled by a fixed minimum damper position does not pass, because the test looks for dynamic control of minimum outdoor air. Uncalibrated instruments are the other common cause — measurement equipment has to be within a year of calibration and the dates recorded.
What it costs when it happens late
More than the correction itself. Retesting means the technician returns, and the failures above are frequently design or programming issues rather than loose wiring — a control zone has to be re-divided, a sequence rewritten, a feature reinstated. Those are not end-of-project changes anyone wants to discover at final inspection.
How to avoid the situation
Identify at design stage which systems will be tested, and design to the test rather than to the specification alone. Zoning that satisfies the occupancy requirement, sequences that control outdoor air dynamically, and daylighting features that survive into the built job are all decisions made long before a technician arrives.